1. Field
The present inventions relate generally to implantable medical devices.
2. Description of the Related Art
Fully implantable infusion devices, which are carried entirely within the patient's body and include a reservoir, a fluid transfer device and a battery, have been used to provide patients with a medication or other substance (collectively “infusible substance”). The reservoir is used to store the infusible substance and, in some instances, fully implantable infusion devices are provided with a fill port that allows the reservoir to be transcutaneously filled (and/or re-filled) through a hypodermic needle. The reservoir is coupled to the fluid transfer device, which is in turn connected to an outlet port. A catheter, which has an outlet at the target body region, may be connected to the outlet port. As such, infusible substance from the reservoir may be transferred from the reservoir to the target body region by way of the fluid transfer device and catheter.
The present inventors have determined that, while generally useful, there are a number of issues associated with conventional fully implantable infusion devices. For example, the present inventors have determined that conventional fully implantable infusion devices are relatively large. In particular, the batteries tend to be relatively large because they must last many years and the reservoirs tend to be relatively large in order to minimize refills, which may necessitate a visit to a physician for a percutaneous needle-based refilling procedure. Another issue identified by the present inventors relates to control. Conventional fully implantable infusion devices are controlled by way of an external remote control which can be lost or misplaced. Another issue identified by the present inventors is maintenance. Should, for example, the catheter be damaged or blocked, surgery is required to remove and replace the catheter.